What counts for identification? Differences in dimensions of social identity between sport teams, families and friendship groups

Following the ideas of social identity theory (sensu Tajfel & Turner) and optimal distinctiveness theory (sensu Brewer), group identification is a function of in-group vs. out-group distinctiveness, in-group similarities, and personal vs. in-group distinctiveness. Based on this tripartite identification definition, the present study aims to find out whether these three parts are of different importance in sport teams compared with other typical group settings (family, friends). 174 sport students (age M = 21.1; SD = 2.1; 48.6 % female) filled out a 12-item questionnaire. 43.7 % participants answered the questions in regard to their sport team (38.5 % family, 17.8 % friends). The scale was theory-driven divided into the three parts group distinctiveness, group similarities, and personal distinctiveness. Each part contained four items regarding properties, attitudes, preferences, and goals of the group respectively the person him- or herself. Since a confirmatory factor analysis failed to prove the theoretical structure the questionnaire was restructured using an exploratory factor analysis. We found three factors group distinctiveness (as theoretically expected), behavioural distinctiveness (preferences, goals), and personal distinctiveness (attitudes, properties). Behavioural and personal distinctiveness were significantly correlated (r = .51). In sport teams behavioural distinctiveness was lower than in families or friendship groups (eta-squared = .23). Furthermore, group distinctiveness was lower in sport teams than in families (eta-squared = .05). Our results show, that group identification in sport teams is especially connected with behavioural homogeneity, which is supposedly correlated to cohesion. Moreover, differentiation from other sport teams is an obviously less important factor.